Driving in the United States: Red Turns, Road Trips, Tolls and Winter Rules
A US road trip can offer great flexibility, but traffic rules vary by state and locality. Learn the rules for your itinerary, particularly conditional turns, school buses, toll arrangements and mountain equipment.
Colorado, United States · packing4two
Rental and insurance
Compare US rentals on DiscoverCars, checking the actual supplier, cover, mileage, additional drivers and one-way returns. Credit-card rental protection does not automatically include liability to other people.
For winter and park routes, confirm required equipment and permission to use it. Canada or Mexico crossings need separate terms and supplier approval.
Driver documents
Bring your original licence, passport, required international permit and a suitable named deposit card. IDP requirements vary by state and supplier; it is not a standalone licence.
Check minimum age, young-driver charges and required licence history. Acceptance in one state does not establish acceptance everywhere.
Miles and limits
Speed Limit signs use mph: 30 mph is about 48 km/h, 55 about 89 and 65 about 105. Check the dashboard scale before driving.
There is no single urban or highway limit for the country. Signs, school-zone conditions, roadworks and weather determine the appropriate speed.
Right-on-red
Many places, including California, permit a right turn on a circular red after a complete stop and yielding unless prohibited. California does not permit a turn against a red arrow.
New York City prohibits turns on red unless a sign expressly permits them. A horn behind you is not an instruction to proceed. Check pedestrians and cyclists; a permitted turn is optional.
Left turns and flashing yellow arrows
A steady green may also release opposing traffic. Yield before turning left across it. A flashing yellow arrow likewise requires yielding; it is not a protected turn.
A green arrow authorises its indicated movement while still requiring care around anyone remaining in the junction. California permits certain one-way-to-one-way left turns on red after stopping and yielding unless prohibited; do not generalise this to all states or intersections.
All-way stops and roundabouts
Stop fully at an all-way stop. Arrival order matters; simultaneous arrivals yield to the right, and left turns must yield to conflicting opposing traffic.
Roundabouts circulate anticlockwise. Follow entry signs and choose a lane in advance. If you miss an exit, continue safely rather than cutting across traffic or stopping suddenly.
School buses
A yellow school bus showing flashing red lights and its stop arm requires stopping, not a careful overtake. Children may cross on either side.
Opposite-direction requirements and divided-road exceptions differ by state. A painted centre line is not the same as a physical median.
Lines and reserved lanes
Yellow lines generally separate opposing directions; white lines separate lanes in the same direction. Diamond markings can identify restricted lanes, with 2+ or 3+ signs indicating occupancy during specified hours.
A shared centre left-turn lane is not for overtaking. An empty express lane may require payment and a specific transponder, even for qualifying carpools.
San Francisco parking
SFMTA meters now accept the HotSpot and ParkMobile apps; PayByPhone has been phased out for this service. Enter the signed location or zone, vehicle and duration and confirm payment.
SFMTA does not accept meter payments through QR codes. Avoid random stickers. Read sweeping days, residents’ restrictions and time limits, and remove visible belongings from the car.
Tolls and the Golden Gate Bridge
Toll systems differ, including Bay Area FasTrak and E-ZPass in other regions. Ask your rental supplier about its arrangement and administration fees to avoid duplicate payment.
The Golden Gate Bridge offers one-time payment up to 30 days ahead or within 48 hours afterwards, subject to rental arrangements. This does not automatically cover every bridge or express lane.
Manhattan and park access
Manhattan’s congestion zone includes local roads south of and including 60th Street, with certain through-road exclusions. The initial peak passenger-car toll is $9 under the applicable payment arrangement; time, billing method and credits affect the actual charge.
National parks may separately require admission, reservations or vehicle restrictions. A parks pass does not guarantee a timed entry or an open mountain road.
Yosemite chains
Carry suitable chains or cables in a designated Yosemite chain-control area, including in rentals and four-wheel-drive vehicles. Some control levels require installation. A supplier not providing chains is not an exemption.
Confirm fit and permitted use and check Yosemite road conditions before departure. Navigation suggestions do not authorise bypassing a closure.
Colorado winter requirements
The I-70 mountain corridor between Dotsero and Morrison has a seasonal arrangement from 1 September to 31 May. Under the updated Traction Law, qualifying AWD/4WD vehicles need appropriately rated tyres with at least 3/16-inch tread, or approved traction devices must be fitted to at least two driven wheels.
Do not rely on an old guide saying every two-wheel-drive car with winter tyres qualifies. Chain Law is stricter. Establish the active restriction and avoid driving beyond the vehicle’s or driver’s capabilities.
Fuel and gallons
A US gallon is approximately 3.785 litres. Pump octane uses AKI: Regular can be 87 and, in some areas, 85. Follow the vehicle’s minimum rather than choosing by the familiar-looking number.
If a foreign card fails a ZIP-code check, pay inside for the correct pump instead of inventing an address. Ask how unused prepayment is returned and retain receipts for rental return.
The Electrify America app
The Electrify America app locates chargers and starts sessions; suitable stations also accept guest card payments. Connect correctly, authorise payment and confirm that power is actually flowing.
Cars may use CCS1, NACS or other standards. Plan compatible alternatives, particularly in deserts and parks, and check time-based or idle charges.
Safe stops and weather
Carry water and fuel or charging reserves in the desert and expect rapid mountain weather changes. Never cross a flooded road or leave children or pets in parked vehicles.
If directed to stop by police, pull over safely, remain inside and keep your hands visible while awaiting instructions. Child-seat, phone and move-over rules vary by state. The emergency number is 911.
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